high phosphorus

Discussion in 'Pesticide & Herbicide Application' started by muddstopper, Sep 28, 2003.

  1. muddstopper

    muddstopper LawnSite Silver Member
    Messages: 2,345

    I posted this in the lawn care forum with out any replies. Maybe someone here has some suggestions.

    overseeding problem
    I have a customer that over fertilized their lawn in june and their lawn started dieing off in a couple of days. Thinking about overseeding using a areo-vator or might just redoe completely. The problem I am having concerns the soil test. Soil testcalls for 118lbs lime per 1000sqft and the phosphorous levels are high off the top of the scale. Nitrogen 4 lbs and potash at 2 lbs per 1000sqft. I plan on putting 50 lbs lime per 1000 when I seed but aint sure what to do about the phosphorus. Area is about 10,000 sqft. Would tilling soil help with the high phos levels. If so I will do a complete redo but, if not I will try the areo-vator and overseed. Any suggestions are apprecated.

    other info:
    1. customer lawn was fescue/ryegrass
    2. customer applied 320 lbs of 10/10/10 fertilizer first of june on area aprox 10,000 sqft
    3.Custome had severe grub infestation and applies seven dust and waters in. seemed to kill gruds as they came to the top of the ground and died everywhere.
    4. Soiltest says to add no phos. to soil. shows the levels to be very high off the scale.
    5. options are 1. power rake lawn and hydroseed using nitrogen only fert. or 2. aerovate and broadcast seed then spray with nitrogen fert.

    Question is will power rakeing lawn stir up enough soil to help phous levels or will I get same results using areovator? Or am I concerned over something that will take care of itself once the grass gets to growing and uses up the phosphorous?
  2. KenH

    KenH LawnSite Bronze Member
    from CT
    Messages: 1,622

    I would think Phosphorous would deplete on its own due to new grass uptake and irrigation which goes along with a new lawn install. Why are you only applying 1/2 the recommended amount of lime??? Do they recommend to do it in 2 steps??? How far was the pH out of whack??
  3. lordohturf

    lordohturf LawnSite Member
    from SW OH
    Messages: 173

    Sounds like the soil is out of whack by the amount of lime required. The high levels of phosphorous in the soil profile may
    be bound in the soil and not released due to extreme low ph.

    Adding a starter fert with seeding shouldn't hurt anything. Adding more phosphorous will perhaps help with easy release to seedling turf. High levels of phosphorous usually do not cause problems.

    Also take a look at cation exchange capacity. If it is very low for your soil type, it may tell you whether phosphorous and other nutrients are bound in the soil.

    Take your choice of seeding processes while keeping in mind the timing is critical at this time of year in the transition zone.
  4. heritage

    heritage LawnSite Bronze Member
    Messages: 1,358

    For starters What are the percentages of the base saturation?
    Ex. Ca,68% Mg,12% K,5% Na, 3% other bases%...and Exchangable hydrogen % ?
    What was the p.p.m. reading of the anion Sulfur?
    Raising P.H. AND having the proper balance of Sulfur will help to mobilize the excess Phos.
    Let me know and I will make a recommendation for you.

    Also it is wise not to add more than 50lbs per 1000ft2 lime at any one time to existing turf. If you need 115 lbs of lime you should make 3 applications a couple of months apart.

    Send the results of base saturation percentage so I can recommend which lime source you should use. High calcium lime (low Mg.) or Dolomitic lime (high Mg.) If you use the wrong lime type your base sat. % may still be off.

    Let me know,
  5. muddstopper

    muddstopper LawnSite Silver Member
    Messages: 2,345

    Lime should never be put out more than 50lb per 1000. Plans are to apply half now and other half in spring.
    almost every soiltest I have done calls for these high amount of lime. The best one I have ever found called for 37 lbs per1000, and it was in an already establish lawn,most are for around 100lbs +/- . Soil type here is mostly ground up shale. The phosphorous levels are high because of the amount of fertilizer already added. When doing new lawns I usually just go ahead and add 40 lbs lime per 1000 with out waiting for the soil test results because 99.9% of the time more lime is going to be needed later anyways. I hate to add more phous making the situation worse, but I am a little afraid not to. Might try for 1 lb per 1000 and test again in spring. Most new soils here call for 4 lbs per year. In fact most soil test results call for 4/4/3.75 for fescue
    Since phous doesnt move readily thru the soil, Will using the areovator help with the CEC by loosening it up so that the water can penetrate better.
  6. muddstopper

    muddstopper LawnSite Silver Member
    Messages: 2,345

    Durn heritage, thats more information than I can digest. here is what the sample says.
    soil ph 5.3
    buffer ph 6.0
    organic matter 2.3
    cec 15.9
    k saturation 2.9
    mg saturation 7.1
    Ca saturation 14.5
    k/mg ratio 1.3
    Ca/mag ratio 3.4
    phosphorus ppm 143
    potassium ppm 178
    magnesium ppm 136
    calcium ppm 462
    recommendations are
    caco/3 109 lbs dolomitic lime
    N= 4.0
    P2 05=0.0

    Test results by Spectrum Analytic for turf type tall fescue
    I goofed when I said 118 lbs of lime it should of been 109lbs
  7. Enviro Green

    Enviro Green LawnSite Senior Member
    Messages: 324

    Phosphorous is bound at very high levels by soils. If you sampled after a fertilization with 320 lbs of 10-10-10, your numbers will be elevated due to the fertiilty treatments.

    Apply starter with seed, that way phosphorous is available to devloping seedlings.

    Lime, as mentionede above, here we always have to use calcitic lime as opposed to magnesium lime

  8. muddstopper

    muddstopper LawnSite Silver Member
    Messages: 2,345

    The fertilizer was applied early June, the soil test was took two weeks ago. Thinking about using a balance blend of fert with 1 lb n/p/k per 1000 sqft. And appling 50lbs Dolo lime per 1000 with 7 lbs turf fescue. Will be using areovator and drop spreader for lime fert and seed. Will be watering in after app. Any more advice is appreciated
  9. turfsolutions

    turfsolutions LawnSite Senior Member
    Messages: 855

    Use calcium based limestone, not dolomitic. Apply at 50lbs per k this fall, next spring, and the following fall. Then retest soil.

    As for Phos. In my area high phos is normal. I would still use phos when you seed, but use a 4 or 5 to 1 ratio of N to Phos the rest of the year. (20-4-4 for example) I am also assuming the N recommendation of 4 lbs per k was over a year span.

    Good luck.

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